This thing is awesome. Has buttons for everything, you can leave it in the case the whole trip until you can dry it off. Took it scuba diving in Catalina, Monterey, and Mendocino and it worked great! Perhaps try photo's with and without strobe (it has the button to turn it off). The case seems to be very well made although I have yet to drop it to find out. I would recommend it to anybody who wants to take some cool water photos!

This product really is wonderful. As other reviewers have noted, the case has a bottom for EVERY camera function. My only complaint, if you can call it a complaint, is that it takes a few minutes to prepare the case. I was hoping for something that you could just throw the camera in and shut the lid and go swimming. Granted, you could probably get away with this, but not if you follow the directions for the case. At any rate, I would certainly recommend this case to anyone who owns a Canon S1 IS. Welcome to water-proof photography.

Unless you are a professional underwater photographer who gets paid for pictures, you probably do not want to shell out $2000 for an underwater case that's likely to be much more expensive than your camera itself. This product lowers the barrier to entry into real underwater photography of up to 130' for <$200. Pair this up with one or two underwater flash lights (which you need anyway if you are going deeper than 30 feet or so), you can have the whole setup for < $1000, since Canon S1 can be had for around $200 now.

Tricks to get good pictures underwater without external flash:
1) Turn off flash (it's useless), turn ISO all the way up.
2) Depending on the type of water you are in, adjust white balance to your likings.
3) Auto-focus works decently if the object is not moving fast. Otherwise you may have to pre-focus or do it manually.
4) Most importantly, have a program that does auto-balance (everything), it does wonders.

I am so very pleased with this purchase. I bought the WP-DC20 for my Canon S1IS for a trip to Hawaii. I had never snorkeled before so it was very exciting to not only see all of the wonderful underwater life but to have photos to show it to my loved ones as well. I learned that you have to get fairly close to the subject in order to get good colors (however, photoshop does wonders for toning down the blue and making the colors show better). I loved that this housing, being made specifically for my camera, allowed me to use all of the functions of the camera. When a sea turtle was peacefully swimming and eating 3 feet in front of me, I was able to quickly switch to movie mode and get some terrific underwater movie clips. You can even hear the noise of the turtle chewing on the coral to get the algae off. If you are a serious underwater photographer, you'll probably want a serious underwater setup with a strobe and all that jazz. If you have the Canon S1IS and love it (I've been so happy with my camera and the prints I've gotten with it) and want to have some underwater fun, this is a terrific toy!

Works great. No leaks. Best advise I can give is don't use the flash. It will only eat up your batteries and scare the fish. Also, learn to use the custom white-balance. Set the short-cut button to the white-balance adjustment function. Then when you're ready to set the white-balance aim the camera at the sun when you're underwater and save the setting. You will need to adjust the setting for every 10 feet of depth change. The custom white-balance setting will make the pictures appear perfect, not washed out in blue. Also, leave the ISO set to auto. Turning it up to 400 causes the pictures to be grainy.

My husband and I bought this prior to our trip to Cancun where we planned to do a lot of snorkeling. We wanted to get the actual case that was made to fit our camera so that nothing would go wrong. We are quite happy with this product. The camera itself takes excellent pictures and the ability to use it in the water was awesome. Throw away cameras can be nice but using our own digital camera was the best. We got lots of great pictures and videos as well.

It was also possible to take pictures out of the water with this case on the camera. For instance, if you were swimming and wanted to take a picture of something when you emerged it was still possible. The only glitch was making sure the lens area was dry on the outside of the case so water spots didn't show up on your picture.

It is a nice case and works well. Since the gasket should not be continuously compressed, it must be stored open, so it is a bit larger to store than I thought it would be.

Even though the Canon S1-IS is now about three models old, my S1-IS still makes it into the luggage when I know there is going to be wet activities thanks to this water-proof case.

The ONLY negative thing I'll say about it is when you shoot video the microphone picks up every little squeek of your fingers on the plastic case, but that's a OK sacrifice to make.. you can always delete the sound and dub-in commentary.

Awesome underwater/all weather case. Absolutley recommend! Sadly my S1 IS recently died, but I am considering buying the S5 IS (or whatever is the lates version when I do) as I LOVED the S1 and still have this waterprrof case.

Not cheap, but worth the money!

This is a great piece of armor for the S100, if you're looking to take pictures fully submerged. It is overkill for casual boating use -- though it would save the camera if dropped in, the S100 shrugs off rain and spray without this protection. Solidly built, large but not too large (still a one-hand camera.) Controls are still convenient. I've mostly used it underwater in swimming pools, but I would have no problem taking it white-water rafting, it feels that sturdy and well-sealed.

For casual use, the Aquapac bag-style case is more economical, but this case is a perfect fit for the camera, and if you do a lot of in-water shooting, would be a much better choice.
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Long after first posting this, I took it along on a trip to Kauai, Hawaii - and successfully grabbed hundreds of pictures of tropical fish and coral in their native habitat. The camera probably spent 20 hours submerged, completely protected, as far as 2 meters below the surface (camera held out at arms length for upward and sideways shots.) It measured up.

I have used abused this case for over a year and it hasn't failed.
After a year or so it gets scratched up and you need to polish it in order to see through the back.

I agree with the previous reviewer (the first I think was referring to the soft case) but I will add a couple of things.

First of all, like the camera itself this case is very high quality. There are two negitives I'll mention:

1. You cannot really use the viewfinder. 1/3 of the view is blocked by the lens housing so you'll end up using the screen and using more battery power.

2. The camera is a TINY bit loose in the case. It will shake just a little bit. It was fixed by ising a small amount of tape on the "rails" that hold the camera. Really no big deal.

The strap is really nice and can be worn like a traditional SLR which is nice for boating or rugged use. Really a neat case if your camera would normally be in danger.

One thing-- I had read a review elsewhere which made it seem like the display could not be turned on or off in the case. Not true, you do have access to the display botton for conserving power.

A case should fit the camera. This does, and I appreciate the secondary pocket that will hold a spare battery and second memory card.

This is a great case--it fits the camera nicely and it allows you to take it underwater and in the rain, snow, etc. But there are few things one should know before buying it:

1. It adds some bulk. It isn't huge, but this probably won't replace your standard carrying case.

2. Some of the functions aren't accessible while using it, such as changing the single/multi/self-timer and you can't put the camera on review mode. You can however change the flash, use the display button, zoom, use macro/infinity.

3. While you CAN use the flash with it, you'll often get some flare from the case itself.

Overall this is a really cool thing to have--but only if you'll use your camera in bad environments--and for this it is perfect.